Way back in July, online retailing giant Amazon dropped an interesting statistic: they were selling Kindle ebooks at a rate of two-to-one when compared to hardcover book sales.

It was a surprising metric, but it wasn’t really clear what it meant: not only is Amazon the only place that sells Kindle books (which would artificially inflate the important of ebooks compared to hardcovers according from Amazon’s perspective) but hardcovers are also relatively unimportant compared to paperbacks, which control most of the market.

Well, six months later, and now Amazon’s Kindle ebooks are outselling hardcovers by three to one, which is amazing but still doesn’t say much. More surprising, though? Kindle ebooks are now outselling paperbacks, at least on Amazon.com. In fact, for every 115 Kindle ebooks sold, only 100 paperback books are purchased on the site.

That’s incredibly impressive. The problem is its still not entirely clear what it all means. Sure, Amazon’s the biggest retailer of paperbacks on Earth, but it’s not the only one, and it’s not even the majority seller. Meanwhile, it’s the exclusive seller of Kindle ebooks. Sure, there’s no doubt, Kindle’s selling like gangbusters… but until Amazon releases some real sales figures, there’s no predicting the death of physical print just yet.